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i • Working To Restore Nature Evaluation of Aquifer Parameters Purpose and Scope RESNA Industries conducted a series of constant-rate pumping tests at the site to evaluate hydrologic and well conditions and provide baseline information for the possible design and operation of a groundwater remedial system The testing program comprised three separate elements designed to provide different types of information The first element consisted of a period of static ground-water monitoring. These data were used to establish initial conditions and to aid the evaluation of the significance of water-level changes observed during the later pumping test The second element of the test program consisted of five short-term constant-rate tests using well PTW-1 This series of tests provided information regarding the well productivity and efficiency The tests were also used to select the rate for the longer-term constant-rate pumping test which constituted the third element of the testing program The long-duration, constant-rate pumping test utilized well PTW-1 for production and wells MW-6, MW-7, and MW-11 as observation wells Data from this test were used to evaluate the hydraulic parameters transmissivity (T) and specific yield (Sy) and to provide information regarding aquifer boundary conditions and anisotropy Test Instrumentation and Format The production well PTW-1 was outfitted with a 4-inch submersible pump which was plumbed through a gate valve and flow meter to a 21,000-gallon storage tank onsite The discharge rate was controlled and recorded manually Drawdown in the pumping well and in observation wells MW-6, MW-7, and MW-11 was recorded both manually with a conductivity probe and automatically using a data pressure logger/transducer system During the first portion of the test program, static water levels in well PTW-1 were monitored for approximately 65 hours This monitoring was conducted to evaluate short term fluctuations in the shallow aquifer under non-pumping conditions Real time plot of the depth to water in PTW-1 is shown on Plate 1-PT The second phase of the test program began with two short-duration constant-rate tests of approximately 2 0 and 5 0 gallons per minute (gpm) The pumping duration of each test was approximately 60 minutes The well was allowed to recover completely between each test During the second pulse test at 5 gpm, significant amounts of silt were produced suggesting the well was still undergoing development After this test, a third pulse test at 3 55 gpm was begun, but we decided to continue this test for the long-term aquifer evaluation Because of the development observed during the second pulse test, two additional 50-minute pulse tests at 2 2 and 4 5 gpm were performed after the conclusion of the long-term test The 38032-10